The present invention relates to an AC plasma display device used for a television receiver, an information display terminal, and other image displays.
FIG. 8 illustrates a panel structure example of a conventional AC plasma display device.
Scan electrode 23 and sustain electrode 24, which are covered by dielectric layer 22, are arranged on front substrate 21 in a pair in parallel. Protect film 25, which is an insulating film easy to be discharged, is formed on dielectric layer 22.
Data electrodes 28 covered by insulating layer 27 are arranged on rear substrate 26. Partitions 29 are located on insulating layer 27 in parallel with and between data electrodes 28. Phosphor layer 30 is formed on a surface of insulating layer 27 and side walls of partition 29. Front substrate 21 and Rear substrate 26 are placed facing to each other sandwiching discharge space 31, so as for scan electrode 23 and sustain electrode 24 to extend in an perpendicular direction to data electrode 28.
Discharge space 31 encloses a mixture of xenon and at least one of helium, neon, and argon as an ionizable gas. One of data electrode 28 and one pair of scan electrode 23 and sustain electrode 24 are arranged to form an intersection region sandwiched by two walls of adjacent partitions 29, and the intersection region corresponds to one discharge cell. Therefore, a plurality of discharge cells 32 are arranged in a plane between front substrate 21 and rear substrate 26.
Next, an operation of the display panel is described.
First, priming discharges occur between all pairs of scan electrode 23 and sustain electrode 24, to accumulate wall charge on a surface of protective film 25.
Second, a scan pulse voltage is applied to one of scan electrode 23, and a write pulse voltage is applied to data electrode 28 corresponding to discharge cell 32 one of display data is written to. This causes write discharge at the discharge cell 32 to do write operation. The write operations are performed to all of scan electrodes 23 in sequence.
After the write operations are done to all of scan electrodes 23, a pulse voltage is applied alternately to all of scan electrodes 23 and all of sustain electrodes 24 to cause discharges at the discharge the cells data are written to. This causes phosphor layers 30 to emit lights. The light emissions perform a panel display.
However, when the above-mentioned operation performs an image display, a write operation failure may not make a cell emit a light, even when the cell should emit a light. In other words, it is known that a non-emitting cell arises in the panel on a random basis and may cause display quality to lower. It is considered that a cause of the write operation failure is a discharge delay phenomenon, which is a general characteristic of a discharge phenomenon.
Generally called a discharge delay is a period between an instance when a voltage higher than or equal to a discharge voltage for a gap is applied across the gap; and an instance when a discharge occurs across the gap. The discharge delay includes a formation delay determined by discharge cell structure and panel formation materials, and a statistical delay reflecting probability factor of the discharge. In particular, the statistical delay is micro second orders of period longer than the formation delay, and becomes a main cause of the write operation failure. On the other hand, a few micro seconds, a rather long, is required to one scan electrode for the write pulse to perform the write operation reliably. Therefore, a ratio of the write operation period to a whole drive pulse period becomes large.
The present invention aims to provide an AC plasma display panel which can reduce a writ operation period and has a high display quality with a reliable write operation by reducing discharge delay in the write operation.
A plasma display panel of the present invention comprises two substrates facing to each other having a plurality of discharge cells arranged in a plane between the two substrates, where each of the cells having an ignition gap, at which a pilot discharge acting as xe2x80x9ca pilot flamexe2x80x9d occurs to stimulate a main discharge. This construction allows a write discharge to occur reliably with the pilot discharge occurring at the ignition gap acting as xe2x80x9cthe pilot flame.xe2x80x9d